README.txt for uCasterisk/unittest/dtmf
Fixed point DTMF detector unit test
David Rowe 18/1/07

HOWTO
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1/ See Makefile for how to build the unit test on a Host PC or Blackfin target.
Then run:

$ ./dtmf_rx_tests

All tests except the last one (Dial tone tolerance) should pass.

2/ To test talk off (false detection of DTMF digits in speech), try running a 
16-bit short 8 kHz file through the detector:

$ ./dtmf_rx_test -s recorded_sample_file.raw

No digits should be detected.

CREDITS
-------

Unit test code & modules (i.e. most of the code in this unit test)
from Steve Underwood's spandsp library.  Thanks Steve.

TODO
----

1. Consider building spandsp for the Blackfin,  rather than just
   using some of the source files as presently implemented.

2. Replace the dsp.c DTMF detector with the spandsp DTMF detector, 
   significant job as the dsp.c version is tightly coupled to dsp.c

3. Some assembler could speed up the DTMF code further.